In a conventional cell, for example the 006P-type cell for producing 9 V, six elemental cells each of 1.5 V are electrically connected in series and are housed in an outer case.
In a 1.5 V-alkaline cell of the cylindrical type, the positive terminal and the negative terminal are respectively located on the top and bottom surfaces of the cell. Therefore, where six alkaline cells of this kind are used as elemental cells and are electrically connected in series to one another, in two rows in each of which three cells are arranged with their positive terminals oriented in the same direction, such arrangement requires a long connecting piece for connecting the negative terminal at the bottom of the elemental cell in one row to the positive terminal at the top surface of the elemental cell in the other row. This arrangement and also requires a long connecting piece for connecting the negative terminal at the bottom of the elemental cell in said other row to the negative terminal disposed at the top surface of the entire cell unit. Thus, such arrangement causes the insulating mechanism and the assembling work to become complicated and troublesome.
On the other hand, where the positive terminals of three elemental cells are oriented in one direction and the negative terminals of other three elemental cells are oriented in said one direction with the respective elemental cells alternately arranged in one line, such arrangement can shorten the lengths of the connecting pieces for connecting the positive terminals of the elemental cells to the negative terminals of the adjacent elemental cells. However, such arrangement that the positive terminals of the respective elemental cells are not oriented in one direction, causes the entire cell structure to become unstable and complicated.
Since the outer case for the 006P-type cell is of the square shape, the use of cylindrical elemental cells presents a disadvantage that the spacial volume of the outer case is increased.
Furthermore, in the 006P-type cell, a large number of elemental cells are required. Each of the elemental cells is adjacent to at least two other elemental cells. In order to prevent undesired electrical contacts between the respective adjacent elemental cells, the respective elemental cells should be covered with insulating sheets, making the assembling of the elemental cells become disadvantageously troublesome.